Ventilated facade insulation



Aug- 18, 1959 s. H. NYCANDER VENTILATED FACADE INSULATION Filed July 8,1955 5 H. /Vycanaer 73 'W7 1r/y.

United States Patent() VENTILATED FACADE INSULATION Sven HildingNycander, Bromma, Sweden, assignor to Internationella Siporex AB,Stockholm, Sweden, a corporation of Sweden Application July 8, 1955,Serial No. 520,887

Claims priority, application Sweden July 15, 1954 1 Claim. (Cl. 72-18)In the erection of buildings, particularly concrete buildings, it iscustomary to improve the heat insulating properties of the externalwalls of the building by mounting light-weight concrete slabs on theoutside of said walls. These light-weight concrete facing slabs mayeither be secured to the walls by mortar or other cement when theconcrete in the wall is already set or they may be inserted in the moldsfor forming an external lling layer therein during the casting of theconcrete forming the external wall so that they are firmly secured tothe concrete.

The facades or external walls insulated in this manner are then usuallycoated with a layer of plaster so that the light-weight concrete slabsare entirely enclosed. In certain cases the outside of the plaster layeris in turn covered with glass mosaic tiles which are secured in theplaster.

Both when the light-weight concrete slabs are secured to the concretewalls either by the adhesion of the concrete mass in the mold or bymeans of mortar spread on the walls and when the outer layer of plasteris applied the light-weight concrete slabs absorb moisture which causesa reduction of their heat insulating capacity and at the same time isydetrimental to the adherence of the plaster to the surface of theslabs. If the external layer of plaster is suiciently porous, it is truethat the insulating layer may dry out slowly under favorable conditions,but if the plaster layer is dense and practically impermeable or when anexternal covering of glass mosaic tiles is used, the moisture iscompelled to remain in the light-weight concrete slabs.

The present invention has for its main object to eliminate thisdisadvantage and to provide a ventilated facade insulation of theabove-mentioned type in a simple manner. The invention thus relates to afacade insulation comprising light-weight concrete slabs mounted on theexternal walls of a building and the main feature of this facadeinsulation according to the invention is that the light-weight concreteslabs included in the facade insulation are provided with grooves intheir `abutting edges so that a network of intercommunicatingVentilating channels is obtained in the insulation, said ventilatingchannels openly communicating with the outer air at the upper and loweredges of the facade insulation.

Generally, the light-weight concrete slabs are placed on the wall insuch a way that said Ventilating channels run in the horizontal andvertical directions, but it is also possible to arrange the light-weightconcrete slabs otherwise with the Ventilating channels forming anglesother than 90, for example, 45, with the horizontal and the verticalplane, respectively.

The invention further relates to a light-weight concrete "ice g 2 slabfor obtaining a ventilated facade insulation' of the type just dened andthe main feature of the said lightweight concrete slab is that it is`provided with longitudinal grooves in at least two of its meeting edgesand preferably in all four of its edges.

The invention now will be more particularly described with reference tothe accompanying drawing showing somewhat dagrammatically and by way ofexample an external wall of a building having an outside insulationaccording to the invention.

In the drawing- Fig. 1 shows front elevation of a part of a facadeinsulated with light-weight concrete slabs and before the application ofthe plaster coating and Fig. 2 shows a partial vertical section throughsuch a facade-insulated external wall in ready-coated condition.

In both gures, 1 is a concrete external wall of a building on theoutside of which a plurality of heat-insulating light-weight concreteslabs 2 are rmly secured and covered externally by a layer of plaster 3and if desired by glass mosaic tiles 4 (Fig. 2). The light-weightconcrete slabs 2 are provided with longitudinal grooves 5 in all theirfour edges, the said grooves forming Ventilating channels 6 entirelyenclosed by the light-weight concrete material in the joints between theslabs 2. The ventilating channels 6 form a network with both horizontaland vertical intercommunicating channel sections and the channel networncommunicates with the outer air both at the upper and lower edges of thefacade insulation as indicated by the arrows 7, as at the upper andlower edges of window apertures and the like. It is, of course,necessary to prevent water and impurities from penetrating into thechannels, which can be effected at the upper edge of the facadeinsulation by allowing the roof 8, a window-sill or the like to projectslightly in the usual manner to hide the upper openings of the channelsin the insulation.

A corresponding ventilation may be obtained when each light-weightconcrete slab is only provided with grooves along two meeting edgesforming an angle to one another, provided that the light-weight concreteslabs are placed uniformly so that the grooves in the different slabsform the `same network wherein they all communicate with each other. Ithas been found desirable to locate the grooves closer to the insides ofthe light-weight concrete slabs than to their outsides in the finishedinsulation since 'then the air current through the Ventilating ychannelswill be stronger thanks to the increased temperature of the completewall nearer the interior of the building. Under all circumstances,however, care must be taken that the grooves do not open on the insidesof the slabs, otherwise the channels will be choked up when casting thewalls or when setting the slabs with mortar on a completed wall unlessspecial precautionary measures are taken.

What I claim is:

A novel Wall construction of a building, the combination which includesan inner sustaining wall, a layer of insulating slabs adhesively bondedto the exterior face of said sustaining wall, one entire face of eachinsulating slab being bonded to a portion of the external surface ofsaid sustaining wall by adhesive mortar, a substantiallymoisture-impermeable continuous coating adhering to the exterior side ofsaid layer of insulating slabs, said insulating slabs being arranged inadjacent edge-to-edge relationship, each of said insulating slabs havinga continuous 3 channel connecting together -the four remaining sides ofsaid insulating slab, saidchannel being isolated -from theaforementioned front and back faces of said insulating slabs, saidchannels in adjacent slabs thus forming a concealed network ofunobstructed intercommunicating 5 Ventilating channels extendingthroughout said layer of insulating slabs, and said network ofunobstructed intercommunicating Ventilating channels opening into theouter air at the upper and lower margins of said insulating layer.

738,643 Van Camp Sept. 8, 1903 1,058,949 Diebel Apr. 15, 1913 1,644,996Grossinger Oct. 1l, 1927 FOREIGN PATENTS 838,949 Germany May 15, 1952

